Not pertinent to your questions, but
    if ( $prompt1 eq ( "y" | "Y" ) ) { ... }
in a few places caught my eye. The bitwise-or of 'y' (ASCII 0x79) and 'Y' (ASCII 0x59) is 'y', so 'Y' will never match.

Win8 Strawberry 5.8.9.5 (32)  Fri 10/16/2020  3:14:29
C:\@Work\Perl\monks
>perl -Mstrict -Mwarnings
my $Y_bitwise_or_y = 'Y' | 'y';
printf "'%s' %#x \n", $Y_bitwise_or_y, ord $Y_bitwise_or_y;
^Z
'y' 0x79
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A common alternative is
    if ($prompt1 =~ /y/i) { ... }

Update: Well, actually... /y/i matches something like 'funky'. IMHO, a better alternative is
    if ($prompt1 =~ m{ \A y }xmsi) { ... }
This case-insensitively matches 'y' 'yy' (I sometimes double-hit keys) 'yes' 'yup' 'ya' etc.
OTOH, m{ \A y \Z }xmsi exactly matches only 'y' 'Y' with or without a newline at the end.